/Engine/Source/Editor/UnrealEd/Public/WorkflowOrientedApp/WorkflowTabFactory.h
Called when a tab created from this factory is sent to the background.
virtual void OnTabBackgrounded ( [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [SDockTab](API\Runtime\Slate\Widgets\Docking\SDockTab) > Tab ) const